bufferHelper("no newlines at all", "no newlines at all");
    bufferHelper("two lines\nbut no newline at end", "two lines\n", "but no newline at end");
    bufferHelper(
        "\nempty first line\nno newline at end", "\n", "empty first line\n", "no newline at end");
    bufferHelper("three\rlines\rno newline at end", "three\r", "lines\r", "no newline at end");

          .put("\\n line break", "hello\nworld")
          .put("\\r line break", "hello\rworld")
          .put("\\r\\n line break", "hello\r\nworld")
          .put("\\n at EOF", "hello\nworld\n")
          .put("\\r at EOF", "hello\nworld\r")
          .put("lorem ipsum", LOREM_IPSUM)
          .buildOrThrow();

  protected final F factory;
  protected final T data;
  protected final T expected;

/*
 * Copyright (C) 2015 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

     * anything interesting under most environments. Still, we can run it (except for Android, at
     * least old versions), so we mostly do. This is useful because we don't actually run our CI on
     * Windows under Java 8, at least as of this writing.
     *
     * Under Windows in particular, we want to test that:
     *

/*
 * Copyright (C) 2015 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

   * first node in insertion order; all values at indices ≥ {@link #size()} are UNSET.
   */
  @CheckForNull private transient int[] predecessor;

  /**
   * Pointer to the successor of an entry in insertion order. ENDPOINT indicates a node is the last
   * node in insertion order; all values at indices ≥ {@link #size()} are UNSET.
   */
  @CheckForNull private transient int[] successor;

   *
   * We'd just use PackageSanityTests directly, saving us from needing this separate type, but we're
   * currently skipping MediumTests on Android, and we skip them by not making them present at
   * runtime at all. I could just make _this_ test a MediumTest, but then it wouldn't run on
   * Android.... The right long-term fix is probably to get MediumTests running under Android by

/*
 * Copyright (C) 2015 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

   *
   * We'd just use PackageSanityTests directly, saving us from needing this separate type, but we're
   * currently skipping MediumTests on Android, and we skip them by not making them present at
   * runtime at all. I could just make _this_ test a MediumTest, but then it wouldn't run on
   * Android.... The right long-term fix is probably to get MediumTests running under Android by

/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,